The present invention relates to ducting and more particularly to an improved flexible duct construction of the kind suitable for use in ducted heating and airconditioning systems for example. The invention also relates to a method of manufacturing the duct.
Many differing forms of duct construction have been used in the past for heating and airconditioning duct construction, as well in the construction of ducts for ventilation and air extraction systems.
More recently some known constructions have been banned for health or safety reasons. For example, ducts constructed of fibreglass are now banned for health reasons and polypropylene foam is not suitable in fire-rated applications. Other constructions which are acceptable for use generally suffer some disadvantage or another such as being costly to produce or requiring expensive raw materials. In most cases, insulating material is added to the duct after the basic duct is constructed.